space physics ppq

Question 2

Why does the moon have phases

Answer 2

• we see the moon due to reflected light from the sun
• this light only illuminates the side facing the sun
• during each phase we see the dark side and part of the light side

Question 3

Why do we never see the other side of the moon

Answer 3

• the moon is rotating on its axis
• the speed of rotation matches the orbital speed (TIDAL LOCKING)

Question 4

what results from the earth taking 24 hours to complete one full rotation

Answer 4

the apparant motion of the sun rising and setting

Question 5

whats reponsible for the periodic cycle of day and night

Answer 5

the rotation of the earth on its axis

Question 6

when would summer be for the northern hemisphere

Answer 6

when the northern hemisphere is tilted towards the earth

Question 7

orbital period

Answer 7

time taken for an object to complete one orbit

Question 8

where is the asteroid belt

Answer 8

between the orbits of mars and jupiter

Question 9

three factors that led to the formation of the planets

Answer 9

• gravity
• many elements in clouds of dust and gas
• forming a disc

Question 10

Similaries and differences between orbits around the sun

Answer 10

Similarities include:
- ellipitical
- in the same plane
- in the same direction
Differences include:
- different distances from the sun
- different speeds
- different orbital periods

Question 11

Describe the process that lead to the formation of planets

Answer 11

The accretion process. Dust left over after the sun was formed contained many heavy elements formed in a supernova explosion. first the dust made a disc which rotated around the sun due to gravity. Slowly the dust began to clump together due to the gravitational attraction between the partcles. The inner planets are rocky because the high temperature near the sun meant that only elements with high melting points existed as solids.